1. Field of the Invention
The present invention relates to an apparatus for collecting grease expelled from a kitchen ventilator, particularly an apparatus for collecting grease expelled from a kitchen exhaust fan of a kitchen ventilator onto the roof of a building housing a restaurant and its kitchen.
2. General Background
Restaurants require a sizable kitchen for cooking. In the process of cooking food for customers, the kitchen generates a large amount of grease. Some of this grease is removed from the kitchen through the kitchen ventilator and expelled through the kitchen exhaust fan of the kitchen ventilator onto the roof of the building housing the restaurant. Accumulation of grease on the roof of the restaurant causes bacteria buildup, fire hazards, pollution, safety hazards, and damage to the roof. Accumulation of grease on the roof of the restaurant may also violate local health and fire department codes, including NFPA 96.
Several devices have been patented which are aimed at preventing grease from accumulating on the roof of a restaurant.
U.S. Pat. No. 2,494,146 issued to P. A. Spanos and entitled "Grease Trapping Device" teaches an inverted cone-shaped grease trapping device 7 that directs excess grease to a central vent pipe 5.
U.S. Pat. No. 4,987,882 issued to Renco Systems, Inc., on the application of A. S. Kaufman and entitled "Roof Mounted Kitchen Hood Grease Exhaust Blowers" discloses a roof-mounted ventilator 10 that extracts grease and deflects it horizontally to a container 66 via discharge scoop 54.
U.S. Pat. No. 2,889,007 issued to K. E. Lunde and entitled "Grease Extracting Ventilator For Kitchen Ranges" discloses a Grease extracting ventilation unit 15 that directs the grease into a trough.
Other patents present in the art are U.S. Pat. No. 3,364,664 issued to D. H. Doane and entitled "Grease Extractor For Ventilating Systems"; U.S. Pat. No. 3,911,895 issued to Cylpik, Inc., on the application of Q. H. Van Schoyck and entitled "Method And Apparatus For Removing Grease From Within An Exhaust System"; U.S. Pat. No. 4,811,724 issued to Halton Oy on the application of E. Aalto, et. al., and entitled "Air Exhausting Means"; U.S. Pat. No. 3,425,334 issued to R. E. Brown, et. al., and entitled "Heat Arresting Grease Extracting Filter Assembly"; and U.S. Pat. No. 2,862,437 issued to G. O. Smith, et. al., and entitled "Ventilating Device", all of which are directed to grease trap filters for ventilation systems and are representative of the state of the art, but do not meet the needs of the apparatus of the present invention.
The Spanos '146 patent relates to a grease trap filter which prevents grease from entering the kitchen ventilator; it does not teach collecting grease that is expelled from the kitchen ventilator through the kitchen exhaust fan onto the roof of the building.
The Kaufman '882 patent teaches directing grease that is expelled from the kitchen exhaust fan to a container. However, the container and the means to direct the grease to the container are not expandable to accommodate a larger amount of grease. Furthermore, the apparatus taught in Kaufman is relatively complex to manufacture and difficult to service and clean.
The Lunde '007 patent teaches directing grease from the kitchen ventilator to a container. However, the apparatus of Lunde collects the grease from the kitchen before the grease reaches the kitchen exhaust fan. Also, Lunde does not teach the problem of the kitchen exhaust fan expelling grease onto the roof of the building. Furthermore, the apparatus taught by Lunde is relatively complex to manufacture and difficult to service and clean.
The Van Schoyck '895 patent teaches placing a removable liner on the inside of the kitchen ventilator to collect grease removed from the kitchen. The Van Schoyck patent does not teach the problem of the kitchen exhaust fan expelling grease onto the roof of the building. Furthermore, the apparatus taught by Van Schoyck is relatively difficult to install and remove.
The remaining prior art patents teach grease filter traps which prevent grease from entering the kitchen ventilator similar to the Spanos '146 patent. They do not teach collecting grease that is expelled from the kitchen ventilator through the kitchen exhaust fan onto the roof of the building. Furthermore, the devices taught in these patents are relatively complex to manufacture and difficult to service and clean.
Accordingly, a need exists for an apparatus that collects grease expelled from the kitchen exhaust fan of a kitchen ventilator onto the roof of a restaurant that is simple in design and easy and inexpensive to manufacture.
Furthermore, a need exists for an apparatus that collects grease expelled from the kitchen exhaust fan of a kitchen ventilator onto the roof of a restaurant that is readily installed and easily removable for inspection, servicing and routine cleaning.
Also, a need exists for an apparatus that collects grease expelled from the kitchen exhaust fan of a kitchen ventilator onto the roof of a restaurant that is expandable to cover and protect a greater area of the roof and to collect more Grease expelled from the kitchen exhaust fan.